Moderator

Just a note that things are getting pretty busy in town, especially over the weekends. If you're about to walk the Camino and you'll be here in Santiago over a weekend, or during June - August, I'd highly recommend reserving your Santiago accommodations now. Even this past weekend many of the albergues were full.
Of course the concept of booking ahead assumes you know when you'll be in Santiago - for example, if you've already booked your flights home and you know you need to make it to town by a certain date. If you're not so sure, then perhaps take a look at accommodations once you're on the trail closer to Santiago to see if it's getting busier or if you can go more with the flow.

Booking.com has a great selection of albergues, pensiones, hostales (private rooms) and hotels at different price ranges. Airbnb.com and Homeaway.co.uk can also be useful sites to seaerch.

I know, Ian, it's not as nice as just walking into town and finding something. The reason I thought to mention it is that the albergues especially are getting full - and that affects mostly pilgrims. The nice thing is that there are a few new albergues that have cropped up in the past couple years - but many of those are outside of old town. So if being closer to the Cathedral is important to folks then they particularly may want to book ahead.

But yes - double-edged sword - a lot more pilgrims on the trail so there are more services all around, but then again there are more pilgrims around who need the same services you need! It's all good, of course .